msm: iomap: remove unused mapping of QGIC_DIST (and QGIC references)

No code is using QGIC_DIST mapping so drop it from being mapped by the
iotable setup code.  Also remove all #define <SOC>_QGIC_* that aren't
used.

Change-Id: I7cce9bedfffb7c30dccb237188193c3ea307ee2e
Signed-off-by: Kumar Gala <galak@codeaurora.org>